CHARLOTTESVILLE, Va., June 21, 2012 –
Kidney injuries among high-school varsity athletes are so rare that
even youth with only one kidney should be allowed to play, researchers
at the University of Virginia School of Medicine have concluded after
conducting a groundbreaking survey of the frequency of such
injuries.

The researchers’ findings, published online in the journal
Pediatrics, shed light on the frequency and severity of kidney
injuries among young athletes. Because of the lack of hard data on the
matter, doctors often recommend that youth with only one kidney not be
allowed to participate in contact sports.

“Many people have restricted that activity in the past because of
concern about the loss of the kidney, but we’ve been able to show that
the risk is really extraordinarily small,” says UVA researcher
Victoria Norwood, MD. “Children with single kidneys – and it’s
important to note normal single kidneys – are really at exceedingly
minimal risk from routine contact sports and therefore should be
allowed to participate as they and their families desire.”Kidney injuries: Hard numbers, small risk
After reviewing more than 23,600 injuries among varsity athletes
reported between 1995 and 1997, the researchers determined there were
only 18 kidney injuries. None was catastrophic or required surgery. In
comparison, there were 3,450 knee injuries and 2,069 head/neck/spine
injuries, in addition to 1,219 cases of mild traumatic brain
injury.

Norwood, Division Chief of Pediatric Nephrology, says she realized the
need for hard numbers after speaking to fellow physicians over the
years. Many told her that they sidelined youth with only one kidney
because they lacked data suggesting it was safe to let them play.
“People were forced to make decisions over the years without any real
evidence,” Norwood says. “I thought it was rather silly to send kids
out to play football with only one spinal cord, one brain and one
spleen but restrict them from the same activity if they had only one
kidney.”The real kidney dangers
She notes that children and teens with only one kidney would be kept
off the gridiron even as they were allowed to engage in other
activities that actually pose much greater kidney risk. “Football seems
to cause the most concern for physicians, not realizing that they were
not restricting downhill skiing, horseback riding or bicycling,”
Norwood says. “Those are activities that are not intended as contact
sports, but the truth of the matter is you do hit things in those
activities, and when you do, the outcome can be quite
catastrophic.”

The most common reason children have only one kidney, she says, is
because of a birth defect. She notes that there is very little chance
that youth sports could generate the force necessary to damage a kidney
severely.

Improving the guidelines
The researchers hope the study results will allow the
American Academy of Pediatrics to offer more specific
recommendations on the subject. The academy’s current stance is a
“qualified yes” on the question of whether athletes with one kidney
should be allowed to play, but that position leaves physicians with
little specific guidance, so most just say no. Norwood says she hopes
the new data will enable the Academy to elaborate so that physicians
will feel more comfortable allowing young athletes to take the
field.

“In today’s world, where kids get too little exercise anyway, we have
an obesity epidemic,” she says. “The last thing we need to do is
discourage exercise of any type, unless there is real evidence behind
that restriction.”